Field of the Invention
The present invention relates to a mechanism for establishing a packet data network connection provided with plural IP addresses. Specifically, the present invention is related to an apparatus, a method and a computer program product which enable to add multiple IP addresses, such as multiple IPv6 prefixes, into a single PDN connection, and to break out IP links from network elements being different to a packet data network gateway or the like.
Related Background Art
Prior art which is related to this technical field can e.g. be found in technical specifications according to 3GPP TS 23.401 (e.g. version 11.3.0).
The following meanings for the abbreviations used in this specification apply:
APN: access point name
BS: base station
CN: core network
CPU: central processing unit
eNB: evolved node B
EPS: enhanced packet system
EUI-64: extended unique identifier 64 bit
ID: identification
IP: Internet protocol
LI PA: local IP access
LLA: link layer address
LTE: Long Term Evolution
LTE-A: LTE Advanced
MME: mobility management entity
NBMA: non-broadcast multiple access
OUI: organizationally unique identifier
PCC: policy and charge control
PDCP: packet data convergence protocol
PDN: packet data network
PDU: packet data unit
PGW: packet date network gateway
RA: radio access
RAB: radio access bearer
E-RAB evolved radio access bearer
RAN: radio access network
RF: radio frequency
SAE: system architecture evolution
SGW: serving gateway
SGSN: serving GPRS support node
SIPTO: selective IP traffic offloading
UE: user equipment
UI: user interface
USB: universal serial bus
WLAN: wireless local area network
In the last years, an increasing extension of communication networks, e.g. of wire based communication networks, such as the Integrated Services Digital Network (ISDN), DSL, or wireless communication networks, such as the cdma2000 (code division multiple access) system, cellular 3rd generation (3G) and fourth generation (4G) communication networks like the Universal Mobile Telecommunications System (UMTS), enhanced communication networks based e.g. on LTE or LTE-A, cellular 2nd generation (2G) communication networks like the Global System for Mobile communications (GSM), the General Packet Radio System (GPRS), the Enhanced Data Rates for Global Evolution (EDGE), or other wireless communication system, such as the Wireless Local Area Network (WLAN), Bluetooth or Worldwide Interoperability for Microwave Access (WiMAX), took place all over the world. Various organizations, such as the 3rd Generation Partnership Project (3GPP), Telecoms & Internet converged Services & Protocols for Advanced Networks (TISPAN), the International Telecommunication Union (ITU), 3rd Generation Partnership Project 2 (3GPP2), Internet Engineering Task Force (IETF), the IEEE (Institute of Electrical and Electronics Engineers), the WiMAX Forum and the like are working on standards for telecommunication network and access environments.
Generally, for properly establishing and handling a communication connection between terminal devices such as a user equipment (UE) and another communication network element or user equipment, a database, a server, etc., one or more intermediate network elements such as communication network control elements, such as base transceiver stations, control nodes, support nodes or service nodes are involved which may belong to different communication network.
In recent communication systems, the ability to communicate not only via one communication network, such as a cellular communication network of which the user of an UE is subscriber, but also via other communication networks having e.g. an IP based access, such as a WLAN or the like, is a common demand.
For example, in 3GPP based communication networks, such as a 3GPP Evolved Packet System (EPS), the bearer and connectivity model from the IP point of view has remained unchanged practically since the birth of General Packet Radio Service (GPRS). That is, the connectivity model boils down to a handful of technical and architectural assumptions, which have remained untouched. The IP connectivity between the mobile device and the network is realized using a point-to-point mimicking link, where the mobile device is assigned with a single /32 IPv4 address and/or a single /64 IPv6 prefix on a single network interface. For a new IP address, an additional connection between the mobile device and the network has to be created, essentially turning the mobile device to a multi-homed host.
Each connection and a connectivity service is always identified by an APN, which in practice names a gateway node such as the PGW providing access to an external Packet Data Networks (PDN), such as the Internet or an (local) operator services network. The gateway node is located in the mobile operator core network (home or visited) and anchors the mobile device and its connection both mobility and IP topology wise. The gateway node also has the function of the first-hop router for the mobile device.
The present connectivity model is working properly in particular when IPv4 was the only realistic IP version and mobile devices were feature phones with a single radio access technology, a limited openness to IP stack for applications and a top down approach for IP connectivity. Applications control the activation of network resources and have a build-in knowledge of what kind of network access they needed (APNs, IP versions and alike).
However, with the emergence of so-called smart phones with a bottom up approach for IP connectivity and the emerging need to solve the practical challenges of multiple network access interfaces on consumer mobile devices, the traditional 3GPP bearer and connectivity model is not optimal anymore.